1. Technical Field
The present invention relates in general to an improved communications system. In particular, the present invention relates to an improved wireless communications system. More particularly, the present invention relates to an improved wireless communications system in which both voice and non-voice data may be transmitted to mobile units over a single dedicated radio frequency channel. Still more particularly, the present invention relates to the manipulation of time intervals or time slots within a single radio frequency channel.
2. Description of the Related Art
Communication networks, such as wireless and wireline telephone systems, are well-known. A typical wireline based communications system utilizes a physical path to transmit signals. Such wireline systems are also referred to as “landline” systems. Examples of wireline communications systems include telephone, telegraph, facsimile, closed circuit television and so forth. Examples of wireless communication systems include cellular telephone systems. A cellular telephone system, in particular, includes cellular subscriber units that can be mobile or portable, and cellular base stations which are connected to the public telephone company via one or more cellular switching networks. Each cellular subscriber has an assigned cellular telephone number which allows the user (i.e., the cellular subscriber) to place and receive calls within a widespread range of the cellular base stations, such as throughout a metropolitan area.
Computerized switching is essential to the operation of both wireline and wireless telephone communication systems. Telephone communication networks typically provide features for redirecting calls on behalf of telephone users. Examples of such features include call forwarding, call transfer, release link trunking; and simultaneous ringing, all well known in the communications arts. Call forwarding, for example, is a network-provided service feature in which calls may be redirected from an originally called address to another address specified by a call forwarding party.
In wireless networks, in particular, it is often desirable to send voice data along with non-voice data, to a mobile unit, such as a mobile cellular telephone. Presently, sending non-voice data to a mobile unit, along with voice data, is a difficult task, due to interference, corruption of the given channel on which the data flows, and limited time slots or time intervals available on such channels. Time division multiplexing (TDMA) is often utilized to send data to mobile units operating within a particular wireless network. TDMA involves the derivation of two or more channels from a single channel by assigning discrete time intervals in sequence to each of the desired channels. In essence, the bandwidth of a particular signal is narrowed or “chopped” up into smaller bandwidths to create multiple channels. Thus, non-voice data associated with voice data can be sent to a mobile unit, but only via separate channels, which is an inefficient waste of signal space.
From the foregoing it can be appreciated then is some sort of method and system which would allow both voice data and non-voice data to ride the same signal, thus freeing other channels for other tasks. What would be desirable would be a method and system which would take advantage of TDMA technology to accomplish this task. However, to date such method and systems do not exist. The present invention disclosed herein solves these problems by implementing a method and system which allows both voice and non-voice data to broadcast over a single dedicated channel.